Startup Equity Dilution Calculator
Simulate cap table dilution across Seed SAFEs, Series A venture rounds, ESOP option pools, and exit valuations.
The Mechanics of Startup Capitalization Tables
Fundraising is an exchange of equity for velocity. Understanding the mathematical compounding of multiple financing rounds prevents founders from experiencing unexpected dilution shocks when preparing for major liquidity events and acquisitions.
Strategic Scenarios
- ✓Co-Founder Equity Allocation Negotiations
Understand the multi-year impact of initial 50/50 vs 60/40 incorporation equity splits once external investors and employee option pools enter the cap table.
- ✓Y Combinator SAFE & Seed Valuation Caps
Calculate the exact ownership percentage relinquished when signing $500k to $2M post-money SAFE agreements with venture capital angels.
- ✓Series A Term Sheet Comparison & Negotiation
Evaluate competing term sheets by modeling pre-money vs post-money valuations and the dilutive effect of investor-mandated 10% to 15% ESOP pool expansions.
- ✓M&A Acquisition & IPO Exit Payout Modeling
Forecast the net monetary dollar value received by each founder, early employee, and venture fund at $50M, $100M, or $500M liquidation events.
Key Capabilities
Multi-Round Sequential Modeling
Models equity evolution from Day 0 Incorporation through Seed SAFE rounds and Series A priced equity rounds.
ESOP Option Pool Shuffle Protection
Accurately isolates whether employee option pools dilute existing founders prior to investment or are shared with incoming investors.
Exit Payout Projection Engine
Calculates exact net dollar distributions across every stakeholder tier at any targeted liquidity or acquisition valuation.
One-Click Cap Table Export
Generates clean cap table summaries ready to paste directly into investor pitch decks, Notion data rooms, or board materials.
Frequently Asked Questions
What is equity dilution in startups?
Equity dilution occurs when a company issues new shares of stock to external investors or an employee pool. While your absolute percentage of the company decreases, the goal is that the total valuation of the company increases, making your smaller percentage worth significantly more in total dollar value.
How does a Post-Money SAFE calculate investor ownership?
With a post-money SAFE (the Y Combinator standard), investor ownership is simply: `Investment Amount / Post-Money Valuation Cap`. For example, investing $1,000,000 on a $10,000,000 post-money cap grants the investor exactly 10.0% of the company immediately prior to the next priced round.
What is the 'Option Pool Shuffle'?
Venture capitalists typically require an unallocated Employee Stock Option Pool (ESOP) of 10% to 15% before investing. In pre-money option pool requirements, this entire pool dilutes the existing founders rather than being split with the new investor. Our calculator accounts for this dynamic.
How much equity do founders typically retain by Series B?
On average, founders collectively own 60% to 70% after Seed, 40% to 50% after Series A, and 25% to 35% after Series B. A smaller percentage of a high-growth company yielding hundreds of millions is vastly superior to 100% of a zero-value business.
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